It were as wise to cast a violet into a crucible that you might discover the formal principle of its colour and odour, as seek to transfuse from one language into another the creations of a poet. The plant must spring again from its seed, or it will bear no flowerand this is the burthen of the curse of Babel.
(Percy Bysshe Shelley (1792-1822), British poet. A Defence of Poetry (written 1821, published 1840).)
He should be as vigorous as a sugar maple, with sap enough to maintain his own verdure,... and not like a vine, which being cut in the spring bears no fruit, but bleeds to death in the endeavor to heal its wounds.
(Henry David Thoreau (1817-1862), U.S. philosopher, author, naturalist. A Week on the Concord and Merrimack Rivers (1849), in The Writings of Henry David Thoreau, vol. 1, p. 101, Houghton Mifflin (1906).)